Insulated conductor



Apnl 16, 1935. .1. PALUcHNlcK INSULATED CONDUCTOR Filed April 6, 1931 Patented Apr. 16, 1935 UNITED STATES PATENT lOFFICE IN SULATED CONDUCTOR igan Application April 6, 1931, Serial No. 527,860

ods of covering conductors and apparatus therefor and more particularly to an improved method of wrapping a covering about a wire conductor 5 and an improved paper wrapping apparatus.

My invention is particularly adapted for covering or insulating magnet wires and the like such as are used to conduct electrical current where it is desired to rapidly and economically cover the wire with an insulating material such as paper and bond the material securely to the wire strand. In the past magnet wire has been covered with wrappings of various materials such as cotton 01 thread. but it has been found that the adjacent strands of such wrappings will separate transversely of the wire at bends and expose the bare wire. By the practice of the method of my invention and the use of my improved wrapping and apparatus the insulating covering will remain intact at the bends despite repeated flexing and will provide a sufficiently smooth and even external surface.

It is an object of my invention to provide an improved insulating covering for a magnet wire or other electrical conductor.

Another object of my invention is to provide in .'nbination with an electrical conductor, an improved covering therefor which will remain intact and in position and retain its original condition undisturbed by bending of the conductor.

Another object of niy invention is to provide. in combination with an electrical conductor, an insulating spiral wrapping which will act to keep the conductor completely covered at bends despite repeated flexing.

Another object of my invention is to provide an improved method of applying an insulating covering to an electrical conductor.

A further object of my invention is to provide an improved apparatus for covering an electrical conductor with an insulating wrapping.

Further objects and advantages of my invention will become apparent throughout a reading of the following detailed description and accompanying drawing, in which- Fig. l is a fragmentary elevational view of a wrapping machine of my invention, parts being broken away to illustrate certain details more clearly.

Fig. 2 is an enlarged perspective view illustrating certain details of the wrapping mechanism.

Fig, -3 is an enlarged plan view taken on the line 3-3 of Fig. 1 illustrating certain details of the wire and paper supply members.

Fig. 4 is a cross-sectional view taken on thc lin'c 4 4 of Fig. 2.

Fig. 5 is an enlarged perspective detail view of the paper folder.

Fig. 6 is an enlarged cross-sectional vicw of a portion of a wire conductor which has been wrapped with paper by the method of my invention, and

Fig. '7 is an enlarged fragmentary cross-section of a portion of a paper wrapped wire conductor before the outer surface has been ironed into final position illustrating the manner in which the paper is folded and lapped.

Referring now to the drawing in detail in which like reference characters designate like parts throughout the several views, the numeral I designates a frame or channel upon which a group or series of wrapping machines II of my invention are mounted. A bearing socket I2 is formed in the top of the channel I0 in which is rotatably mounted the lower end of a hollow spindle I3. The spindle is mounted on and keyed in some suitable manner to a vertically disposed hollow shaft I4 which is rotatably mounted in the frame Ill. A beveled gear I5 secured on the 25 shaft I4 is in engagement with a beveled gear I6 connected with the line shaft I'I which is rotated by any suitable source of power not shown. A suitable hand controlled clutch I8 serves to afford a means of disconnecting the beveled gears and associated shafts from the power driven line shaft I'I when desired. The spindle I3 is thus rotated in the direction indicated by the arrows in Figs. 1, 2 and 3. The shaft I4 is hollow as is the spindle I3 which has a bore 9 extending throughout its length to allow passage of a strand of magnet wire I9 or other electrical conductor upon which the insulating paper is to be wound as illustrated in Figs. 1, 2 and 3. The magnet wire I9 is wound about a suitable supply reel 20, which is mounted in any suitable manner (not shown in the drawing), and passes over a pulley 2| which centers the wire directly below the hollow shaft I4 and spindle I3. A glue pot 22 of any suitable design is mounted on the underside of the frame I0 by brackets 23 and has an opening 24, of the size of the wire which is being wrapped, inthe bottom thereof to allow passage of the wire.

The spindle I3 has a platen 25 formed thereon, as best shown in Fig. 2, upon which a roll of paper 26 is placed which is to be wrapped about the wire I9. The hollow spindle I3 is cut in half section at 8 to expose the wire I9 from the top of the platen up to the top of the spindle I3. A

paper folder 21 of v-shaped design is flared outwardly at one end to receive the paper and reduced to form a neck 28 through which the folded paper passes onto the wire I9. 'I'his V- shape paper folder 21 has a cylindrical bearing 29 formed thereon which is adapted to reciprocate upon a vertically disposed rod 39 secured in the platen 25. A corresponding lvertical rod @I is mounted parallel to the rod 30 on the platen 25 and in close proximity thereto and is adapted to be engaged by the neck 28 of the paper folder which slides thereon'as will hereinafter be described.

A cylinder 32 is mounted on the platen 25 and surrounds the spool of paper 26 and the wrapping mechanism, acting as a guard and retainer for the paper spool 26. Guide eyelets 33 are formed on the inner wall of the cylinder 32 through which the strip of paper 2G is threaded which is to be wound about the wire I9, as best shown in Fig. 3. These guides properly position the strip of paper as it enters the V-shaped channel of the paper folder 21. The paper is then threaded through the paper folder 21 and folded to pass through the neck 28 and be wound about the wire I9. The paper is twisted one-half turn as it passes into the V-slot, which thereafter folds it over and as it passes through the flat neck 28 it is pressed and creased in folded position. It has been found desirable to so thread the paper through the folder that a small portion of one edge thereof will remain single or unfolded for the purposes to be hereinafter described.

A spring pressed ironing member 35 is rotatably mounted on a rod 36 secured in the platen 25 and extending vertically upward therefrom. A4 spring 31 surrounds the rod 36 and has one end 38 thereof in engagement with the spindle I3 and the other end 39 engaging a groove 49 in the iron 35. The iron is thus spring pressed against a guide member dl which is rotatably mounted on the top of the spindle I3 and has a at surface d2 thereof which is adapted to cooperate with the ironer 35. It will be noted that the internal diameter of the spindle bore at 8 from the platen up to the guide member'lli is relatively greater than the internal diameter of the bore in the member el through which the conductor passes. The purpose of the larger diameter of the spindle bore is -to prevent any kink in the wire from shearing the wrapping between the point where it is applied and the lower edge of the member 4I due to rubbing on the interior surface of the spindle bore. The member d! is short enough to allow the wire to slip through, even though kinked without shearing.

The covered wire I9 is wound up on a takeup spool or reel 42 after the paper has been Wrapped thereon, which spool is driven by any suitable source of power (not shown) whereby the wire` I9 is drawn upwardly through the spindle i3. A

` cylindrical supply container A3 surrounds the wire I9 above the wrapping mechanism and is retained in position in any suitable manner (not shown). The container43 is open at the bottom and adapted to retain an extra supply of paper rolls 26 which may be held in position by removable spring clips or some other suitable securing means.'

The operation of my device is as follows:

When the power is turned on the spindle I3 is revolved at a rapid rateV in the direction indicated by the arrows and the wire I9 is moved upwardly through the hollow spindle. As the wire passes throughthe glue pot 22 it receives a thin coat of glue and as it continues upwardly through the hollow spindle shaft, the paper is wrapped therearound in spiral fashion because of the rotation of the spindle. The entire cylinder easing 32, paper spool 26 and platen 25 of the spindle with its associated paper folder 2`I -and ironer 35 revolves at a high rate of speed about the wire I9. The paper on the roll is in unfolded condition and is folded upon itself as it passesA through the V-shaped paper folder 21 and fed through the neck 28 and thereafter is wrapped about the wire I9 by the rotation of the spindle I3. The speed of travel of the wire I9 is properly synchronized in proportion to the rate of revolution of the spindle I3 whereby the paper will be wrapped or Wound about the wire I9 in spiral fashion with the upper doubled edge of the paper overlapping the lower single edge of the preceding spiral wrapping. The spring pressed ironer 35 will rotate about the wire I9 and press the paper tightly against the wire, insuring a smooth external contour on the surface of the' covering and pressing the paper tightly against the glue coated wire to securely bond it thereto. When it becomes necessary to reload the wrapper after the paper roll 26 is. entirely used up, a fresh roll of paper may be slipped down from the container 63, which surrounds the wire I9, onto the platen 25 and be threaded through the eyelets 33 and paper folder 21 onto the wire I9 without the necessity of severing the wire or materially interrupting the operation.

Referring to Figs. 6 and 7 in detail it will be noted that the paper is folded upon itself by the folder 21 but not entirely so, the lower edge of the paper remaining uncovered, that is, the paper is not completely doubled but is of single thickness at itsllower edge with respect to its position when wrapped upon the wire i9. The amount of lap of the folded portion of the paper upon itself is controlled by the width of the slot in the neck 28 of the folder 21. The wire I9 is moved at a rate which allows the paper to be lapped over and cover the unfolded or single edge of the preceding spiral or wrapping, as illustrated in Fig. '1. The purpose of this arrangement is to insure a smooth external contour to the paper which is obtained by the pressing iron 35 which presses the overlapping double portion of the paper tightly against the lower single edge..

The wrapping is therefore of three thicknesses of the paper at the points of overlap, instead of 'four thicknesses, as would be the case if the paper were completely doubled upon itself. It is believed that this arrangement allows a slight sliding motion or flexing of the upper and lower layers of the doubled paper and a telescoping of the adjoining layers when the wire is bent, which prevents cracking, scufling or parting of the Wrapping.

A conductor covered with insulation in the -manner herein described presents a three ply Wrapping formed from a single piece of paper which substantially covers the wire. The wrapping is formed of a series of short pitched spirals which remain in position and are less inclined to unravel than spirals of longer or steeper pitch. The wire may be covered with a three ply insulation by short pitch spirals because of the doubling of the wrapping material.

Since the top of each spiral presents an edge which has been folded double and the single bottom edge is covered by each succeeding spiral, the exposure of a raw edge is therefore prevented.

It is believed that the action of the wrapping is as followsz-When the wire is bent or flexed the two outer plies of the wrapping may flex and slide relative to each other and relative to the outer surface of the lower edge of the preceding spiral which is bonded to the wire by the cement, thus completely covering at all times the raw or unfolded bottom single edge of each spiral. The flexing or bending of the wire is compensated for in the three ply insulation by a sliding and telescoping of the two folded outer layers with respect to each other while the lower unfolded single edge is always tightly pressed against the wire by the two outer folds of the insulation.

Regardless of whether or not the action is precisely as above described it is known by actual experience' in the use of insulated conductors covered in the manner and bythe method and apparatus herein described that the results lare substantially as set forth, the advantages claimed are actually attained, and the objects of my invention are accomplished by the wrapping described.

It will be noted that the paper folder may reciprocate vertically upon the rod 30 as the wrapping mechanism rotates about the wire I9, thus eliminating possibilities of breakage of the paper due to unevenness in width or position on the roll which would otherwise cause tearing when the mechanism is operated at a high rate of speed. The guide rod 3| maintains the paper folder in proper relation to the wire i9 by preventing rotation of the folder through engagement with the neck 28. l

A plurality of such wrapping mechanisms may be mounted on the frame I0 and connected with the same source of power by the line shaft Il using suitable clutches I8 in the same manner as that just described.

It will be readily apparent that various changes may be made in the constructioi.- and arrangement of the wrapping mechanism herein described without departing from the spirit and scope of the invention, the form herein described being merely a preferred embodiment thereof.

I claim:

1. In combination with an electrical conductor,

an insulating spiral wrapping thereon comprising,v

a strip of material folded double throughout a portion of its width being unfolded the remainder of its width, the doubled portion being superposed over the unfolded portion of the adjoining spiral.

2. In combination with an electrical conductor, an insulating spiral wrapping thereon comprising, a strip of material partly folded double and having a single unfoldedfmargin constituting the remainder of the strip and extending beyond the doubled portion, said margin being slightly offset with respect to said doubled portion, said doubled portion being superposed over the single unfolded margin of an'adjoining spiral. i

3. In combination with an electrical conductor, an insulating spiral wrapping thereon comprising, a strip of material partly folded double with the remainder forming a single margin extending beyond the doubled portion, said doubled portion being superposed over and pressed inwardly upon the single margin of each preceding spiral to dispose the single margin and doubled portion in slightly offset relation.

4. An electrical conductor having a multiple ply insulating spiral wrapping therefor comprising, a single strip of insulating material folded two ply throughout a portion of its Width having a single ply margin forming the remainder of its width and disposed along one edge thereof, said two ply portion being superposed over the single ply margin of an adjoining spiral.

5. An electrical conductor having a multiple ply insulating spiral wrapping therefor comprising, a single strip of insulating material folded two ply throughout a portion of its width having a single ply margin forming the remainder of its Width and disposed along one edge thereof, said two ply portion being superposed over the single ply margin of each preceding spiral and in telescopic engagement therewith.

6. An electrical conductor having a three ply insulating spiral wrapping therefor comprising, a strip of paper folded two ply along one edge and having a single ply margin along one edge, the inner surface of the single ply margin being bonded to the conductor, a part of the two ply portion of each spiral completely covering the single ply margin of the preceding spiral and the inner surface of the remaining part of the two ply portion being bonded to the conductor.

7. In combination with an electrical conductor, an insulating spiral wrapping thereon comprising, a strip of material folded double along one edge only and being unfolded the remainder of its width, the doubled portion being superposed over the unfolded portion of the adjoining spiral.

8. In combination with an electrical conductor, an insulating spiral. wrapping thereon comprising a strip of material folded double along one edge only with a single margin extending beyond the double portion throughout the remainder of its width, said doubled edge portion being superposed over substantially the entire single margin of each preceding spiral.

9. An electrical conductor having a multiple ply insulating spiral wrapping therefor comprising, a single strip of insulating material folded two ply along one edge only, the remaining portion of its width constituting a single ply margin, said two ply portion being superposed over and pressed inwardly upon substantially all of the single ply margin of an adjoining spiral to present a finished insulating wrapping of substantially uniform thickness throughout its entire length.

JOSEPH PALUCHNICK. 

